Maximum User ID Issue

[akaracing]

Hi,
We found that if you set the AUTO_INCREMENT value to 18446744073709551614 (which is 1 less than the maximum value of BIGINT), it creates a blank user in the admin user table. upon checking the mySQL database details, we found that the ID (_users) is 18446744073709551614 and the user_id (_usermeta) is 9223372036854775807. the reason for the test is, we have created a plugin that allows an admin to change the user ID of any user, so we where testing the maximum upper limits of. The only way to delete this user is manually, the delete option fails.

it would seem the ID (_users) supports 0 to 18446744073709551615
and
it would seem the user_id (_usermeta) supports -9223372036854775808 to 9223372036854775807

this can be checked in ​https://dev.mysql.com/doc/refman/5.5/en/integer-types.html

thanks

[SergeyBiryukov]

Related: #17945, #22845.